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Previous issue date: 2011-02-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / This study proposes to find a biodiesel through transesterification of rice bran oil
with KI/Al2O3 checking the influence of two types of alumina (Amorphous and Crystalline)
for conversion into methyl esters. The catalyst was synthesized by the wet impregnation
method. Adding 30 mL of 35% KI(aq.) in 10 g of alumina, under stirring at 80 ?C for 3 hours.
The reaction conditions used in this study were optimized, with a molar ratio methanol:oil of
15:1, 8 h of reaction time and reflux temperature. The catalyst amount was varied in the range
of 1 to 5 % wt. The solid catalysts materials were analyzed by: x-ray diffraction (XRD),
thermogravimetry (TG), N2 adsorption/desorption, scanning electron microscopy (SEM) and
basicity, for the identification of its structure and composition, verifying the presence of basic
sites. The results showed that Al2O3(A) presents an amorphous structure, high surface area
and a better catalytic activity, in relation to the catalyst synthesized with Al2O3(C) support
that proved to have a more crystalline structure, having as well, a lesser surface area, enabling
difficulties for the incorporation of active sites. The obtained biodiesel with 5% wt.
KI/Al2O3(A) presented physicochemical properties within the standards specified by the
Resolution No 7/2008 ANP and obtained the best reaction yield with 95.2%, according to
quantitative measurement from the TG, which showed 96.2% conversion into methyl esters. It
was furthermore found that with the increasing amount of the quantity of the catalyst in the
reaction, there was also an increase in the ester content obtained. The specific mass and the
kinematic viscosity were reduced with the increase of the amount of quantity of the catalyst,
indicating an increase in the conversion of triglycerides / Esse estudo prop?e-se a obter um biodiesel a partir da transesterifica??o do ?leo de
farelo de arroz com KI/Al2O3 verificando a influ?ncia de dois de tipos de alumina (Amorfa e
Cristalina) na convers?o em ?steres met?licos. O catalisador foi sintetizado pelo m?todo de
impregna??o via ?mida. Adicionando 30 mL de uma solu??o de 35% KI(aq.) em 10 g de
alumina, sob agita??o constante a 80?C por 3h. As condi??es reacionais utilizadas nesse
estudo foram otimizadas, como raz?o molar de metanol:?leo de 15:1, tempo reacional de 8hs
e temperatura de refluxo. A quantidade de catalisador foi variada na faixa de 1 a 5% wt. Os
materiais s?lidos catal?ticos foram analisados por: difra??o de raios-X (DRX), an?lise
termogravim?trica (TG/DTG), adsor??o/dessor??o de nitrog?nio, microscopia eletr?nica de
varredura (MEV) e teste de basicidade para identifica??o da estrutura e sua composi??o,
verificando a presen?a de s?tios b?sicos. Os resultados mostraram que Al2O3(A) apresenta
uma estrutura amorfa, alta ?rea superficial e uma melhor atividade catal?tica em rela??o ao
catalisador sintetizado com o suporte Al2O3(C) que mostrou-se uma estrutura mais cristalina,
menor ?rea superficial, dificultando a incorpora??o dos s?tios ativos. O biodiesel obtido com
5% wt. KI/Al2O3(A) apresentou propriedades f?sico-qu?micas dentro das normas especificadas
pela resolu??o N?7/2008 da ANP e o melhor rendimento da rea??o com 95,2%, em
conformidade com a medida quantitativa a partir da TG, que exibiu 96,2% de convers?o em
?steres met?licos. Foi verificado que com o aumento da quantidade de catalisador na rea??o,
aumenta o teor de ?steres obtidos. A massa espec?fica e a viscosidade cinem?tica foram
reduzidas com o aumento da quantidade de catalisador, indicando um aumento na convers?o
dos triglicer?deos
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/17642 |
| Date | 25 February 2011 |
| Creators | Evangelista, Jo?o Paulo da Costa |
| Contributors | CPF:35530502415, http://lattes.cnpq.br/9770622597949866, Pergher, Sibele Berenice Castella, CPF:50942611004, http://lattes.cnpq.br/5249001430287414, Coriolano, Ana Catarina Fernandes, CPF:83744479404, http://lattes.cnpq.br/5552621403067808, Souza, Luiz Di, CPF:01925100880, http://lattes.cnpq.br/0589648773241934, Ara?jo, Ant?nio Souza de |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Qu?mica, UFRN, BR, F?sico-Qu?mica; Qu?mica |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/openAccess |
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